Drama: An Architecture For Accelerated Processing Near Memory

Improving energy efficiency is crucial for both mobile and high-performance computing systems while a large fraction of total energy is consumed to transfer data between storage and processing units. Thus, reducing data transfers across the memory hierarchy of a processor (i.e., off-chip memory, on-chip caches, and register file) can greatly improve the energy efficiency. To this end, we propose an architecture, DRAMA, that 3D-stacks coarse-grain reconfigurable accelerators (CGRAs) atop off-chip DRAM devices. DRAMA does not require changes to the DRAM device architecture, apart from through-silicon vias (TSVs) that connect the DRAM device's internal I/O bus to the CGRA layer. We demonstrate that DRAMA can reduce the energy consumption to transfer data across the memory hierarchy by 66-95 percent while achieving speedups of up to 18 x over a commodity processor.